05000298/LER-2009-005, Regarding High Pressure Coolant Injection Governor Valve Failure
| ML100490174 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 02/11/2010 |
| From: | Dori Willis Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2010010 LER 09-005-00 | |
| Download: ML100490174 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| 2982009005R00 - NRC Website | |
text
N Nebraska Public Power District "Always there when you need us" NLS2010010 February 11, 2010 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Licensee Event Report No. 2009-005-00 Cooper Nuclear Station, Docket No. 50-298, DPR-46
Dear Sir or Madam:
The purpose of this correspondence is to forward Licensee Event Report 2009-005-00.
Sincerely, Demetrius L. Willis General Manager of Plant Operations hJo Attachment cc:
Regional Administrator w/attachment USNRC - Region IV Cooper Project Manager w/attachment USNRC - NRR Project Directorate IV-1 Senior Resident Inspector w/attachment USNRC - CNS SRAB Administrator w/attachment NPG Distribution w/attachment INPO Records Center w/attachment SORC Administrator w/attachment CNS Records w/attachment COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3871 / Fax: (402) 825-5271 www.nppd.com
Abstract
On December 21, 2009, Cooper Nuclear Station Control Room Operators started the High Pressure Coolant Injection (HPCI) auxiliary oil pump in support of obtaining an oil sample for the predictive maintenance oil analysis program. Immediately following the start of the auxiliary oil pump, the Control Room Operator observed that the HPCI governor valve did not respond as expected. The HPCI auxiliary oil pump was operated a second time and the governor valve did not operate at all. As a result, HPCI was declared inoperable at 13:37, Central Standard Time (CST), resulting in entry into Technical Specification Limiting Condition of Operation (LCO) 3.5.1 Condition C, and LCO 3.3.3.2 Condition A.
Preliminary results of the troubleshooting activities determined that the malfunctioning governor valve could be a result of binding in the electro-hydraulic controller (EG-R). The EG-R has been sent to an offsite laboratory for analysis. The cause of the event will be provided in a supplemental report after the results of the analysis have been reviewed.
This event was determined to be reportable as a loss of safety function. Actual nuclear safety significance is minimal due to the fact that no events occurred which required HPCI to be initiated. HPCI was declared operable at 16:45 CST on December 24, 2009.
NRC FORM 366 (9-2007)
(If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of Form 366A)
Actual nuclear safety significance was minimal from the standpoint that no events occurred that relied upon HPCI initiation. This is a Safety System Functional Failure.
CAUSE
Results of the root cause evaluation will be provided in a supplemental report after results of the laboratory analysis have been reviewed.
CORRECTIVE ACTION
Corrective actions will be provided in a supplemental report after results of the laboratory analysis have been reviewed.
PREVIOUS EVENTS A review of CNS Licensee Event Reports (LER) from 2006 to present revealed that there was one other occurrence related to a loss of safety function due to HPCI being declared inoperable. On February 7, 2007, HPCI inverter circuit failure alarms were received intermittently indicating a loss of the inverter output. The failure was the result of an intermittent open circuit in the inverter caused by corrosion which resulted from solder flux residue remaining on copper conductors during the manufacturing process. The event was reported under LER 2007-001, dated April 5, 2007, with a supplemental report, LER 2007-001-01, submitted on May 23, 2007.
ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS© 4 ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS©4 Correspondence Number:
NLS2010010 The following table identifies those actions committed to by Nebraska Public Power District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory
commitments
Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITMENT
COMMITTED DATE
COMMITMENT
NUMBER OR OUTAGE None 4
4 4
4 4
4 4
4 4
4
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